// Copyright 2014 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef V8_COMPILER_BACKEND_GAP_RESOLVER_H_
#define V8_COMPILER_BACKEND_GAP_RESOLVER_H_

#include "src/compiler/backend/instruction.h"

namespace v8 {
namespace internal {
    namespace compiler {

        class GapResolver final {
        public:
            // Interface used by the gap resolver to emit moves and swaps.
            class Assembler {
            public:
                virtual ~Assembler() = default;

                // Assemble move.
                virtual void AssembleMove(InstructionOperand* source,
                    InstructionOperand* destination)
                    = 0;
                // Assemble swap.
                virtual void AssembleSwap(InstructionOperand* source,
                    InstructionOperand* destination)
                    = 0;
            };

            explicit GapResolver(Assembler* assembler)
                : assembler_(assembler)
                , split_rep_(MachineRepresentation::kSimd128)
            {
            }

            // Resolve a set of parallel moves, emitting assembler instructions.
            V8_EXPORT_PRIVATE void Resolve(ParallelMove* parallel_move);

        private:
            // Performs the given move, possibly performing other moves to unblock the
            // destination operand.
            void PerformMove(ParallelMove* moves, MoveOperands* move);

            // Assembler used to emit moves and save registers.
            Assembler* const assembler_;

            // While resolving moves, the largest FP representation that can be moved.
            // Any larger moves must be split into an equivalent series of moves of this
            // representation.
            MachineRepresentation split_rep_;
        };

    } // namespace compiler
} // namespace internal
} // namespace v8

#endif // V8_COMPILER_BACKEND_GAP_RESOLVER_H_
